Early 2008 24" iMac With Possible Graphics Issue?

I've got an early 2008 iMac 24" C2D 2.8 GHz with the NVIDIA GeForce 8800 GS video card installed that has started acting up. Initially it was just the occasional hang or beach ball that never went away and now we are starting to see some odd graphic issues. See enclosed image below. The system locked up hard shortly after taking this screenshot. There was nothing particular running at the time (no games).

I can't consistently recreate the issue in the screenshot below, but if I load a game such as StarCraft II the system locks up hard.

I seem to remember that some of the NVIDIA chips had issues, but is anyone aware of issues with the GeForce 8800 GS video card used in the early 2008 iMac8,1?

Are there any graphics tests or benchmarks I can run to confirm there is an issue with my GeForce 8800 GS video card?

Staff Member

Have you tried reseting SMC and PRAM? Apple hardware check from the install disc? 8600M GT has had the most issues and Apple is even covering them but 8800 GS hasn't got any special treatment. I've seen few failures similar to yours before though

I sure hope not. I got one of those imacs with that graphics card last year, but it's 3.06 ghz. Ive done intense gaming and editing on it, and its always been smooth but the thing is, is that people who have had these iMacs have said that the graphics card has almost always failed which worries me. The question I have for you though is, why does it say 100% charged at the top lol?

Have you tried reseting SMC and PRAM? Apple hardware check from the install disc? 8600M GT has had the most issues and Apple is even covering them but 8800 GS hasn't got any special treatment. I've seen few failures similar to yours before though

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Thanks for the tips Hellhammer. I've reset the SMC and PRAM and run the extended HW diagnostic test from my OS X install discs. No issues found. Starcraft II still locks up the system when it hits the loading screen. It has run successfully in the past.

I do have bootcamp and WinXP installed so next I might try running Starcraft II from there and see if I encounter the same issues. If I don't encounter the same issue under WinXP perhaps it is just an OS X issue and I can try reinstalling the OS.

Installed StarCraft II under WinXP and experienced similar issues with graphical anomalies under WinXP, so I took the iMac into the Apple store today.

The Apple technician ran some tests and found some things that made him believe there was a graphics card issue so Apple is replacing my graphics card under AppleCare. Should have the iMac back in a week.

Hopefully with the new graphics card everything will be back to normal.

wow, not another one.. we're not the only ones with this problem! Unfortunately I don't have Apple care (my computer is 2 1/2 years old by now) and the same problem arose with my 3.06 GHZ 24" iMac (Mac OX 10.6.5, 4GB RAM, Nvidia 8800 GS, 512GB HD).

After doing tons of research online i've found that there are MANY people out there with this issue. Unfortunately some kid who works at the Apple store compared my iMac to a car and said that sometimes things break and need to be replaced. That is hilarious because as a hobby I work on auto mechanics so I just laughed when he told me that.. Typical line he sells to customers probably.

I love apple products but after owning 7 macs, 2 iPhones, and several other accesories and apple software including using every version of mac os from 6.x.x to 10.6.x, this endeavor has been pretty disappointing. There is a serious flaw in these graphics cards it is obvious... I use the iMac primarily for email and web, with the occasional Starcraft II game (usually run not more than 1 hour at a time). I used an external fan on the iMac from time to time when I felt it would get hot to the touch (top left corner of the case). So I tried preventing any heat damage as much as possible. Unfortunately, even after installing iStat Pro and seeing that my GPU, CPU, HD temps were all in the normal range, I still had graphical artifacts and constant freezing and lockups. It got worse and worse and to the point where booting up was not an option. Took it to the apple store and within 2 minutes the guy knew it was the graphics card (did he really need to run a test? It's blatantly obvious). His attitude towards me was rude and very cold. He was rushing me to take my iMac to the back and have me drop 600$ to fix it like money was nothing for me. I had to tell him to hold on and let me think about this because graphics cards don't brake for nothing. That's when he told me I should have thought about that before not buying applecare. I was upset at the guy but didn't show it as I did not want to create a scene and make apple's reps look bad cuz I love apple and I was frustrated at this kid rather than at apple at this point. I think apple does stand by their products and I hope that they can offer some sort of fix for this rather than having us dish out this money out of our own pockets because of a design flaw (lack of sufficient cooling internally) with their products that cost roughly 3000$.

In response to this kid's comparison of my iMac to cars needing repairs: Apple is like the BMW of computers. Top of the line. Quality parts. If you buy a BMW and don't race it and daily drive it, if after 2 years your engine fails because it overheated because the fans weren't built to cool the engine sufficiently, normally BMW would issue a recall, no? Or atleast offer to replace the part as a good will for their design flaw? I would think that Apple would do the same...

Got my iMac back from Apple today. Apple replaced the Nvidia 8800 GS graphics card. I brought my iMac home right way, plugged it in, hit the power button and no startup tone. Finally a gray screen comes up and then after about a minute a globe appears in the middle of the gray background.

I've never seen this one before so I call the Apple store back and explain the situation and am referred to the Genius desk and speak with someone who says it sounds like my iMac was left in network boot mode. That I should give it a little time. I guess it will eventually start from the internal HD when no network boot option is found.

Sure enough after about five minutes it boots from the HD and comes up normally. I login, go to System Preferences and change the start up disk to the OS X internal disk. I learned something new with this one.

So next I start StarCraft to test out the new graphics card and the games starts downloading an update. During this time I go and fix myself some tea and when I come back the screen is blank. Figuring the display just went to sleep I tap the keyboard... Nothing. I move the mouse... Nothing. I put my ear to the top of the monitor and I can hear the fans running, but no response to any input from the keyboard or mouse and the screen is black. I try a hard reset with the power button and no start up tone or anything on the screen. I can hear the fans startup, the DVD and then the HD spin up, but nothing else.

To make a long story short I call Apple Care and go through every possible action to try and get a response out of my iMac, but no luck. I'm headed back to the Apple store today to drop my iMac off once again.

hm what can i say ..sorry and you are not the first and certainly not the last , but its not unexpected the nvidia 8800 the letters behind make no real difference , had been just smaller then the competition , and most important for apple cheaper then the competitions cards , but offered the most performance for the money too , but gets quiet warm and the components on the card absolute do not like any form of heat which is no issue if people have this card in a deskop pc tower with plenty of cooling , then this card may last a lifetime , but in the small space the card has in the iMac....a couple degree can make a huge difference in the lifespan of components , thats the reason why lots of people use smc fan control and others to rev up the fans to near full speed when gaming especially with nvidia 8800 iside its advisable to rev up the graphics fan to full speed , the iMac is just not a gaming rig , but its fine as long as you got apple care apple will replace the faulty cards, but will apple acknowledge that its a problem ...no

i personally build gaming rigs as a hobby and since years avoid nvidia like the devil holy water in anything that is not watercooled and running windows

Got my iMac back from Apple today. Apple replaced the Nvidia 8800 GS graphics card. I brought my iMac home right way, plugged it in, hit the power button and no startup tone. Finally a gray screen comes up and then after about a minute a globe appears in the middle of the gray background.

I've never seen this one before so I call the Apple store back and explain the situation and am referred to the Genius desk and speak with someone who says it sounds like my iMac was left in network boot mode. That I should give it a little time. I guess it will eventually start from the internal HD when no network boot option is found.

Sure enough after about five minutes it boots from the HD and comes up normally. I login, go to System Preferences and change the start up disk to the OS X internal disk. I learned something new with this one.

So next I start StarCraft to test out the new graphics card and the games starts downloading an update. During this time I go and fix myself some tea and when I come back the screen is blank. Figuring the display just went to sleep I tap the keyboard... Nothing. I move the mouse... Nothing. I put my ear to the top of the monitor and I can hear the fans running, but no response to any input from the keyboard or mouse and the screen is black. I try a hard reset with the power button and no start up tone or anything on the screen. I can hear the fans startup, the DVD and then the HD spin up, but nothing else.

To make a long story short I call Apple Care and go through every possible action to try and get a response out of my iMac, but no luck. I'm headed back to the Apple store today to drop my iMac off once again.

Took my iMac back to the Apple store today. The tech that helped me at the Genius Bar tried to boot it a couple times, reset the SMC and even tried reseating my RAM but no luck.

He told me they are going to replace the main logic board and the GPU this time and I should have it back around the middle of next week or so. He also said that after they got it back together they would run a program to stress the GPU for 24 hours to ensure it is in good working order before I get it back.

Took my iMac back to the Apple store today. The tech that helped me at the Genius Bar tried to boot it a couple times, reset the SMC and even tried reseating my RAM but no luck.

He told me they are going to replace the main logic board and the GPU this time and I should have it back around the middle of next week or so. He also said that after they got it back together they would run a program to stress the GPU for 24 hours to ensure it is in good working order before I get it back.

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Good luck man. I had that done to my imac and after 1.5 weeks I brought my imac back to the same genius again for the same issue.

Took my iMac back to the Apple store today. The tech that helped me at the Genius Bar tried to boot it a couple times, reset the SMC and even tried reseating my RAM but no luck.

He told me they are going to replace the main logic board and the GPU this time and I should have it back around the middle of next week or so. He also said that after they got it back together they would run a program to stress the GPU for 24 hours to ensure it is in good working order before I get it back.

Click to expand...

If it has problems after that, I'd start demanding a replacement. If they won't I'd sell it for as much as you can get and buy the current ATI models.

I am confused. Your signature shows that you have a 27" iMac i5. Your "About Me" thing on your profile shows a 24" iMac. Did they replace your iMac with a newer model or something? Is your 24" under warranty?

I am confused. Your signature shows that you have a 27" iMac i5. Your "About Me" thing on your profile shows a 24" iMac. Did they replace your iMac with a newer model or something? Is your 24" under warranty?

wow, not another one.. we're not the only ones with this problem! Unfortunately I don't have Apple care (my computer is 2 1/2 years old by now) and the same problem arose with my 3.06 GHZ 24" iMac (Mac OX 10.6.5, 4GB RAM, Nvidia 8800 GS, 512GB HD).

After doing tons of research online i've found that there are MANY people out there with this issue. Unfortunately some kid who works at the Apple store compared my iMac to a car and said that sometimes things break and need to be replaced. That is hilarious because as a hobby I work on auto mechanics so I just laughed when he told me that.. Typical line he sells to customers probably.

I love apple products but after owning 7 macs, 2 iPhones, and several other accesories and apple software including using every version of mac os from 6.x.x to 10.6.x, this endeavor has been pretty disappointing. There is a serious flaw in these graphics cards it is obvious... I use the iMac primarily for email and web, with the occasional Starcraft II game (usually run not more than 1 hour at a time). I used an external fan on the iMac from time to time when I felt it would get hot to the touch (top left corner of the case). So I tried preventing any heat damage as much as possible. Unfortunately, even after installing iStat Pro and seeing that my GPU, CPU, HD temps were all in the normal range, I still had graphical artifacts and constant freezing and lockups. It got worse and worse and to the point where booting up was not an option. Took it to the apple store and within 2 minutes the guy knew it was the graphics card (did he really need to run a test? It's blatantly obvious). His attitude towards me was rude and very cold. He was rushing me to take my iMac to the back and have me drop 600$ to fix it like money was nothing for me. I had to tell him to hold on and let me think about this because graphics cards don't brake for nothing. That's when he told me I should have thought about that before not buying applecare. I was upset at the guy but didn't show it as I did not want to create a scene and make apple's reps look bad cuz I love apple and I was frustrated at this kid rather than at apple at this point. I think apple does stand by their products and I hope that they can offer some sort of fix for this rather than having us dish out this money out of our own pockets because of a design flaw (lack of sufficient cooling internally) with their products that cost roughly 3000$.

In response to this kid's comparison of my iMac to cars needing repairs: Apple is like the BMW of computers. Top of the line. Quality parts. If you buy a BMW and don't race it and daily drive it, if after 2 years your engine fails because it overheated because the fans weren't built to cool the engine sufficiently, normally BMW would issue a recall, no? Or atleast offer to replace the part as a good will for their design flaw? I would think that Apple would do the same...

Click to expand...

Do not give on this. Push apple to honor this. They know those nvidia chips are defective and should repair or replace your machine. If you don't get anywhere at the apple store call customer care and escalate this.

Perhaps a 3D benchmark that runs under OS X, although I don't know of one off the top of my head. When I got my iMac back the first time I started up StarCraft II and had a go at it. In my case I didn't get very far.

Still waiting to get my iMac back. Called the Apple store yesterday to get a status update and they said they were still waiting on the MLB to arrive. Oh well... Looks like I might not get it back until next week at this point.

Thanks for the input, I will research a 3D Benchmark test to push it and let you know what I find.

I got the iMac home last night, hooked it up, ran a backup to be on the safe side, and then I used my eyeTV to record a few shows. No problems but the top left of the mac was HOT... I am going to push it like crazy this weekend and see how it reacts to the stresses.

I am sure everyone who has experienced this issue would agree with me when I say I have little faith in the reliability of my machine for the long term and that to me is a just as bad as it breaking down.

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